在胡说之前,首先声明,本文是建立在掌握php单文件上传的基础上,所以这里就不赘述文件上传服务器配置,表单设置该注意的地方了。
话不多少,直入主题,在请求页面方面有两种写法(只呈现表单部分,以上传三个文件为例。)
<span><</span><span>form </span><span>action</span><span>="doAction.php"</span><span> method</span><span>="post"</span><span> enctype</span><span>="multipart/form-data"</span><span>></span><span> 请选择我的上传文件 </span><span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfile[]"</span><span>/></span> <span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfile[]"</span> <span>/></span> <span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfile[]"</span> <span>/></span> <span><</span><span>input </span><span>type</span><span>="submit"</span><span> value</span><span>="上传"</span> <span>/></span> <span></</span><span>form</span><span>></span>
<span><</span><span>form </span><span>action</span><span>="doAction.php"</span><span> method</span><span>="post"</span><span> enctype</span><span>="multipart/form-data"</span><span>></span><span> 请选择我的上传文件 </span><span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfil1"</span><span>/></span> <span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfil2"</span><span>/></span> <span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfil3"</span><span>/></span> <span><</span><span>input </span><span>type</span><span>="submit"</span><span> value</span><span>="上传"</span> <span>/></span> <span></</span><span>form</span><span>></span>
两个对比,发现仅仅是name的不同,第一个将name设置成数组的形式,而第二个则是我们通常设置也很容易想到的一种方法。
虽然表面上显示的仅仅有一点点不同,但真正提交到doAction.php页面的$_FILES则有很大不同。
第一种的$_FILES是一个三维数组,而第二种是二维数组,如下:
function getFiles(){ foreach($_FILES as $file){ $fileNum=count($file['name']); if ($fileNum==1) { $files=$file; }else{ for ($i=0; $i $fileNum; $i++) { $files[$i]['name']=$file['name'][$i]; $files[$i]['type']=$file['type'][$i]; $files[$i]['tmp_name']=$file['tmp_name'][$i]; $files[$i]['error']=$file['error'][$i]; $files[$i]['size']=$file['size'][$i]; } } } return $files; }
通过这个函数,将$_FILES转化为下面格式:
此刻,两种上传方式已经处在同一起跑线了,下面的工作便是编写uploadFile()函数对每个文件进行上传,这也是本文的重点。
文件上传函数:
<span>function</span> uploadFile(<span>$file</span>,<span>$path</span>='./uploads',<span>$max_size</span>,<span>$allowExt</span><span>){ </span><span>$filename</span>=<span>$file</span>['name'<span>]; </span><span>$type</span>=<span>$file</span>['type'<span>]; </span><span>$temp_name</span>=<span>$file</span>['tmp_name'<span>]; </span><span>$error</span>=<span>$file</span>['error'<span>]; </span><span>$size</span>=<span>$file</span>['size'<span>]; </span><span>if</span> (<span>$error</span>==<span>UPLOAD_ERR_OK) { </span><span>if</span> (<span>$size</span>><span>$max_size</span><span>) { </span><span>$res</span>['mes']=<span>$filename</span>."文件超过规定上传大小"<span>; } </span><span>$ext</span>=getExt(<span>$filename</span><span>); </span><span>if</span> (!<span>in_array</span>(<span>$ext</span>, <span>$allowExt</span><span>)) { </span><span>$res</span>['mes']=<span>$filename</span>.'文件名不合乎规范'<span>; } </span><span>if</span> (!<span>is_uploaded_file</span>(<span>$temp_name</span><span>)) { </span><span>$res</span>['mes']=<span>$filename</span>."文件不是通过HTTP POST 方法上传上传过来的"<span>; } </span><span>if</span> (@<span>$res</span><span>) { </span><span>return</span> <span>$res</span><span>; } </span><span>if</span> (!<span>file_exists</span>(<span>$path</span><span>)) { </span><span>mkdir</span>(<span>$path</span>,0777,<span>true</span><span>); </span><span>chmod</span>(<span>$path</span>, 0777<span>); } </span><span>$fname</span>=<span>getUniName(); </span><span>$destination</span>=<span>$path</span>.'/'.<span>$fname</span>.'.'.<span>$ext</span><span>; </span><span>if</span> (<span>move_uploaded_file</span>(<span>$temp_name</span>, <span>$destination</span><span>)) { </span><span>$res</span>['mes']=<span>$filename</span>.'上传成功'<span>; </span><span>$res</span>['dest']=<span>$destination</span><span>; }</span><span>else</span><span>{ </span><span>$res</span>['mes']=<span>$filename</span>."文件上传失败"<span>; } }</span><span>else</span><span>{ </span><span>switch</span> (<span>$error</span><span>) { </span><span>case</span> '1': <span>$res</span>['mes']="超过了配置文件上传文件的大小"<span>; </span><span>break</span><span>; </span><span>case</span> '2': <span>$res</span>['mes']="超过表单设置上传文件文件的大小"<span>; </span><span>break</span><span>; </span><span>case</span> '3': <span>$res</span>['mes']="文件部分被上传"<span>; </span><span>break</span><span>; </span><span>case</span> '4': <span>$res</span>['mes']="没有文件被上传"<span>; </span><span>break</span><span>; </span><span>case</span> '6': <span>$res</span>['mes']="没有找到临时目录"<span>; </span><span>break</span><span>; </span><span>case</span> '7': <span>$res</span>['mes']="文件不可写"<span>; </span><span>break</span><span>; </span><span>default</span>: <span>$res</span>['mes']="上传文件失败"<span>; </span><span>break</span><span>; } } </span><span>return</span> <span>$res</span><span>; }</span>
其中还涉及了两个小函数:
<span>/*</span><span>* * 获得文件扩展名 * @param string $filename 上传文件名 * @return string 返回扩展名 </span><span>*/</span> <span>function</span> getExt(<span>$filename</span><span>){ </span><span>$arr</span>=<span>explode</span>('.', <span>basename</span>(<span>$filename</span><span>)); </span><span>return</span> <span>end</span>(<span>$arr</span><span>); } </span><span>/*</span><span>* * 获得文件唯一扩展名 * @return string 经过md5后生成32位唯一的上传文件名 </span><span>*/</span> <span>function</span><span> getUniName(){ </span><span>return</span> <span>md5</span>(<span>uniqid</span>(<span>microtime</span>(<span>true</span>),<span>true</span><span>)); }</span>
感受:
很久前接触过php文件上传,当时感觉一团乱麻。现在看来只要掌握$_FILES里面包含什么信息,利用自己写过的知识处理一些小技巧,系统有逻辑的加以考虑,适时地封装函数,以后文件上传就可以很快地展开。这次我展现的代码必然不是能满足任何需要,所以可以适当改造,成为自己的代码。比如如果要求上传文件是图片内容的话,单靠扩展名是绝对不能判断的,还需要利用图片的特性加以验证。